The Town hall is old and would cost a fortune to heat. There's no doubt it would be expensive to insulate, install triple-glazed windows, and set up solar panels on the roofs. However, local architects and the Engineering College are willing to work on my proposed redevelopment for free. I recommend that one section be converted into office space - that would help offset the cost of the project.
Redevelopment would benefit everyone
It's not hard to see who would benefit from demolition - property developers who would buy the land cheaply and throw up some copy/paste housing. Modernising the building and re-opening the meeting spaces would benefit not only the people who would meet there but also the whole community. It would be a focal point and we could hold weddings and rent space for family gatherings by giving the building a new modern function.
Conclusion
I believe that modernising the building is the best choice and strongly urge you to consider it.